Siemens Burner Sequence Controller LME11.230C2

Product Details

The Siemens LME Series is a range of microprocessor-based burner controls designed for the supervision of 1- or 2-stage gas or gas/oil burners. These controllers have largely replaced the older LGB and LMG series and are known for their high reliability and precise digital signal processing. 1. Key Features of the LME Series Undervoltage Detection: Ensures the burner shuts down if the power supply drops below a safe level. Air Pressure Supervision: Provides a functional check of the air pressure switch during startup and operation. Multicolor LED Status: The reset button changes color (Green, Yellow, Red) to indicate the current phase of the burner or fault codes. Intermittent Operation: Designed for burners that cycle at least once every 24 hours. Remote Reset: Features an electrical remote lockout reset facility. 2. Model Breakdown (Type Summary) The model number specifies the burner stage and specific timing requirements ($t_1$ = pre-purge time, $TSA$ = ignition safety time). Model Series Application Common Models LME11 1-stage gas burners, typically up to 120 kW. LME11.230C2, LME11.330C2 LME21 2-stage gas burners, with control for an actuator. LME21.130C2, LME21.330C2 LME22 2-stage gas burners, often used with forced draft. LME22.231C2, LME22.331C2 LME41 Atmospheric gas burners (single stage). LME41.051C2, LME41.091C2 LME7 Modular platform for medium to large capacity burners. LME71.000A2, LME73.000A2 3. Full Technical Specifications These specs apply to the core LME1/2/4 series: Mains Voltage: 230V AC (Standard) or 120V AC (indicated by C1 suffix). Power Consumption: Approx. 12 VA. Flame Monitoring: Ionization Probe: Standard for gas flames. UV Detector: Uses QRA... (requires AGQ3... ancillary unit for 230V systems). Blue-Flame Detector: Uses QRC... detectors. Degree of Protection: IP40 (when installed correctly). Operating Temperature: -20°C to +60°C. Designed Lifetime: 250,000 startup cycles (approx. 10 years in normal heating mode). 4. Diagnostic LED Codes When the unit enters "Lockout" (Solid Red LED), you can diagnose the issue by the number of pulses: 2 Pulses: No flame established at the end of safety time ($TSA$). 3 Pulses: Faulty air pressure switch (e.g., switch stuck in the "open" position). 4 Pulses: Extraneous light during startup (flame signal detected when it shouldn't be). 7 Pulses: Loss of flame during operation. 10 Pulses: Wiring error or internal unit failure. 5. LME7 (The Advanced Platform) For industrial applications, the LME7 is used. It features: Plug-in Program Modules (PME): Allows you to change the burner logic by simply swapping a small module. 7-Segment Display: Shows the exact phase of operation or error code digitally. Communication: Includes a BC interface for connecting to a PC (via OCI410) or an AZL2 display unit.